1. Field of the Invention
The present invention relates to the field of biomedical engineering and medical treatment of diseases and disorders. More specifically, the invention relates to devices and methods for destroying aberrant cell masses, including tumor tissues, such as cancerous tissues of the brain.
2. Description of Related Art
Treatment of abnormal cell growth in or on normal body tissues and organs can be achieved in many different ways to achieve reduced cell growth, reduction of the resulting aberrant cell mass, and even destruction of the aberrant cell mass. In general, treatments known in the art involve surgical intervention to physically remove the aberrant cell mass, radiation to kill the cells of the aberrant cell mass, exposure of aberrant cells to toxic chemicals (i.e., chemotherapy), or a combination of two or all three of these. While each treatment modality has shown significant effectiveness in treatment of various cell proliferative diseases, no one technique has been shown to be highly effective at treating all types of cell proliferative diseases and disorders. Furthermore, each technique has significant drawbacks. For example, surgical intervention is highly effective at removal of solid tumors on tissues and organs that are physically accessible and capable of sustaining physical damage or capable of regeneration. However, surgical intervention can be difficult to perform on tumors that are not readily accessible or on organs that do not regenerate (e.g., brain tumors), and can involve substantial physical damage to the patient, requiring extensive recuperation times and follow-on treatments. Likewise, treatment with radiation can result in collateral damage to tissue surrounding the tumor, and can cause long-lasting side-effects, which can lower the quality of life of the patient. Similarly, chemotherapeutic treatments cause systemic damage to the patient, and can result in significant side-effects that might require a long recuperation period or permanent damage to the patient.
In the treatment of tumors, including malignant tumors, it is recognized in the medical arts that it is important to achieve ablation of the undesirable tissue in a well-controlled and precise way without affecting the surrounding healthy tissue. The inventors and their colleagues recently developed a new method to treat tumors, known as irreversible electroporation (IRE). The procedure involves placing electrodes within or near the targeted region to deliver a series of low energy, microsecond electric pulses for approximately 1 minute. These pulses permanently destabilize the cell membranes of the targeted tissue (e.g., tumor), thereby killing the cells. IRE does not affect major blood vessels, does not require the use of drugs and non-thermally kills neoplastic cells in a precise and controllable manner, without significantly damaging surrounding tissue. The inventors and their colleagues also recently showed the complete regression in 12 out of 13 treated tumors in vivo using IRE on a type of aggressive sarcoma implanted in nude mice (Al-Sakere, B. et al., 2007, “Tumor ablation with irreversible electroporation.” PLoS ONE 2.).
Although advances have been made recently in the field of IRE and the concept of treatment of tumors with IRE has been established, the present inventors have recognized that there still exists a need in the art for improved devices and methods for ablating diseased or disordered tissues, such as tumor tissues, using IRE. The present invention addresses those needs.